DETROIT -- Economists are debating whether the U.S. is headed for deflation -- broadly declining prices that, if they got out of hand, could worsen into a spiral of vanishing profit margins and postponed purchases.

There's nothing academic about this debate for Beth Ardisana. She runs a firm called ASG Renaissance that provides contract labor to Ford Motor Co. Ms. Ardisana and her managers have had to inform about 150 workers that their wages will drop 7% across the board. The cut is a response to a mandate from Ford that all...